Detectionhightest

Webshell Detection With Command Line Keywords

Detects certain command line parameters often used during reconnaissance activity via web shells

Convert In Phoenix Studio

Open this Sigma rule in the converter with the YAML preloaded and ready for backend selection.

Florian Roth (Nextron Systems), Jonhnathan Ribeiro, Anton Kutepov, oscd.community, Chad Hudson, Matt AndersonCreated Sun Jan 01Updated Sat Dec 14bed2a484-9348-4143-8a8a-b801c979301cwindows

Log Source

WindowsProcess Creation

ProductWindows← raw: windows

CategoryProcess Creation← raw: process_creation

Events generated when a new process is spawned on the system. Covers command-line arguments, parent/child relationships, and process metadata.

Detection Logic

detection:
    selection_webserver_image:
        ParentImage|endswith:
            - '\w3wp.exe'
            - '\php-cgi.exe'
            - '\nginx.exe'
            - '\httpd.exe'
            - '\caddy.exe'
            - '\ws_tomcatservice.exe'
    selection_webserver_characteristics_tomcat1:
        ParentImage|endswith:
            - '\java.exe'
            - '\javaw.exe'
        ParentImage|contains:
            - '-tomcat-'
            - '\tomcat'
    selection_webserver_characteristics_tomcat2:
        ParentImage|endswith:
            - '\java.exe'
            - '\javaw.exe'
        CommandLine|contains:
            - 'catalina.jar'
            - 'CATALINA_HOME'
    selection_susp_net_utility:
        OriginalFileName:
            - 'net.exe'
            - 'net1.exe'
        CommandLine|contains:
            - ' user '
            - ' use '
            - ' group '
    selection_susp_ping_utility:
        OriginalFileName: 'ping.exe'
        CommandLine|contains: ' -n '
    selection_susp_change_dir:
        CommandLine|contains:
            - '&cd&echo'  # china chopper web shell
            - 'cd /d '  # https://www.computerhope.com/cdhlp.htm
    selection_susp_wmic_utility:
        OriginalFileName: 'wmic.exe'
        CommandLine|contains: ' /node:'
    selection_susp_powershell_cli:
        Image|endswith:
            - '\cmd.exe'
            - '\powershell.exe'
            - '\pwsh.exe'
        CommandLine|contains:
            - ' -enc '
            - ' -EncodedCommand '
            - ' -w hidden '
            - ' -windowstyle hidden'
            - '.WebClient).Download'
    selection_susp_misc_discovery_binaries:
        - Image|endswith:
              - '\dsquery.exe'
              - '\find.exe'
              - '\findstr.exe'
              - '\ipconfig.exe'
              - '\netstat.exe'
              - '\nslookup.exe'
              - '\pathping.exe'
              - '\quser.exe'
              - '\schtasks.exe'
              - '\systeminfo.exe'
              - '\tasklist.exe'
              - '\tracert.exe'
              - '\ver.exe'
              - '\wevtutil.exe'
              - '\whoami.exe'
        - OriginalFileName:
              - 'dsquery.exe'
              - 'find.exe'
              - 'findstr.exe'
              - 'ipconfig.exe'
              - 'netstat.exe'
              - 'nslookup.exe'
              - 'pathping.exe'
              - 'quser.exe'
              - 'schtasks.exe'
              - 'sysinfo.exe'
              - 'tasklist.exe'
              - 'tracert.exe'
              - 'ver.exe'
              - 'VSSADMIN.EXE'
              - 'wevtutil.exe'
              - 'whoami.exe'
    selection_susp_misc_discovery_commands:
        CommandLine|contains:
            - ' Test-NetConnection '
            - 'dir \'  # remote dir: dir \<redacted IP #3>\C$:\windows\temp\*.exe
    condition: 1 of selection_webserver_* and 1 of selection_susp_*